# DB50X — Color version of DB48X

> High-precision scientific calculator with advanced features and arbitrary precision. (iPhone/iPad app by Christophe de Dinechin.)

- Source: https://appshunter.io/ios/app/db50x/id6625971367 (this page in markdown: same URL + `.md`)
- Developer: [Christophe de Dinechin](https://appshunter.io/developer/1761608161)
- Category: Productivity, Education
- Price: $9.99
- Rating: 5.00/5 from 8 App Store ratings · 4 written reviews indexed
- Age rating: 4+
- Requires: iOS 14.0 · 7 MB
- Languages: American English
- Released: 2024-08-19
- Data updated: 2026-08-24
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/db50x/id6625971367/reviews.md

## What is DB50X?

DB50X is a new high-precision scientific calculator inspired by the legendary HP50G series from Hewlett-Packard.
It is not an emulator, but a redesign from scratch, which is faster, and delivers never seen before capabilities like computations in arbitrary precision.

Like the original HP50G, DB48X supports an unlimited stack, RPN and algebraic operations, complex numbers, based numbers, vectors, matrices, text, symbolic computations, numerical solving and integration, graphing and plotting, statistics, engineering units, and well over 1000 built-in functions. It integrates a library of equations and constants covering mathematics, physics or chemistry.

Using modern technologies, DB50X goes well beyond the original HP50G in many ways:
- It is significantly faster, uses less memory, and features a higher-resolution 240x400 pixels graphical color display.
- Integer and decimal values can have an arbitrarily large number of digits, so you can compute log(pi) with 200 digits in a few keystrokes.
- The six function keys feature up to three function per key, giving quick access to up to 18 related functions at a time.
- Complex numbers can mix and match polar and rectangular form.
- Symbolic operations extend to complex numbers, vectors and matrices.
- Based numbers can be in any base from 2 to 36, and support any number of bits, making it easy to emulate a 23-bit or 512-bit processor.
- Text is represented using Unicode instead of the proprietary HP encoding, facilitating data exchange with the rest of the world.
- Multiple graphs can be distinguished using colour patterns
- Engineering units include all the modern evolutions of the SI system, and can be configured by the user, e.g. to integrate currency units with the exchange rate du jour. Converting between USD/hour and EUR/day has never been so easy!
- A built-in hyperlinked help system documents functions simply by holding the corresponding key, and combine a quick start guide, a user manual and a reference manual.
- Over 700K of memory is available for RPL programs.
- Access to iCloud to save your program and edit them from your Mac.

DB508X will run many user RPL programs designed for the HP48, HP49 or HP50 directly as is.
However, since it is not an emulator, it will not run any HP binary object, and notably will not run HP50G games or anything involving system RPL.

This is an early-access release. Please consult https://github.com/c3d/db48x/blob/stable/doc/5-Unimplemented.md for a list of commands that are not yet implemented.
DB50X is part of a family of related calculators that include the black-and-white DB48X and the entry-level DB40X.

## Key features

- Arbitrary precision calculations
- RPN and algebraic operations
- Complex numbers, vectors, matrices
- Symbolic and numerical solving
- Graphing and plotting
- Engineering units and constants
- Unicode text support

## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/db50x/id6625971367/reviews.md

### 5/5 — Greatest evolution of great HP calculators of the past.  Wish there were a Windows PC emulator.

*2026-03-07*

Christophe, would it be possible to create a Windows PC emulator of the DB50X?  It would be helpful for me to have this open when working in 3D CAD.

### 5/5 — Some keypad confusion

*2025-04-11*

The 1/x key should have e^x top left yellow and ln top right blue. The root x key should have x root y top right blue. Edit c.

### 5/5 — Not an HP48 clone, better!

*2024-11-23*

This guy started trying to make something similar to the HP48 family of calculators, but is ending up with something better.  It is designed to be installed on a swissmicro calculator, but this IOS app works the same and is nicer than the other HP48/50 emulators.

### 5/5 — Goodbye HP 28s —> HP50g… Hello DB50X

*2024-10-20*

Finally we are getting a modern calculator that carries forward the brilliance of the HP 28s family.  Great work with the unit conversions and looking forward to creating a family of equations that can share common variables!  Then I can put my tired HP50g that away with my original HP28s!  I’m finding that the innovative menu system is intuitive and quickly familiar.   Thanks

## Frequently asked questions about DB50X

### What makes DB50X different from a standard calculator app?

DB50X offers arbitrary precision for calculations, meaning you can compute with an unlimited number of digits. It also includes advanced features like symbolic computations, complex number operations in polar and rectangular forms, and extensive graphing capabilities.

### Can DB50X run programs from older HP calculators?

DB50X can run many user RPL programs designed for HP48, HP49, or HP50 directly. However, it is not an emulator and will not run any HP binary objects or system RPL, such as games.

### How does DB50X handle complex numbers?

Complex numbers in DB50X can mix and match polar and rectangular forms. Symbolic operations also extend to complex numbers, providing advanced manipulation capabilities.

### What kind of display does DB50X have?

DB50X features a high-resolution 240x400 pixels graphical color display. This allows for clear visualization of graphs and multiple colors to distinguish them.

### Is DB50X available on multiple devices?

Yes, DB50X is supported on iPhone, iPad, and iPod. It also integrates with iCloud for saving and editing programs on your Mac.

### How often is DB50X updated?

The latest version is 0.9.17, last updated on March 10, 2026. This indicates a recent and active development cycle for the application.

### What is the pricing for DB50X?

DB50X is a paid application, available for $9.99. This one-time purchase provides access to all its advanced scientific calculation features.

### Does DB50X have ads?

No, DB50X does not contain advertisements. As a paid application, it offers an ad-free experience for uninterrupted use.

## Version history (last 5 releases)

### 0.9.19 — 2026-05-25

This release brings an improved constants library with Astronomy and Materials sections, the Quote command, GCD and LCM commands, and several other improvements.

See release notes (https://github.com/c3d/db48x/releases/tag/v0.9.19) for details.

### 0.9.18 — 2026-04-17

New features:
* Implement the `Chuck` command
* Make `xq` recognize more patterns during simplification
* List the menus in the help file
* Support for tables in the help file
* `ListRecursionDepth` setting for `map`, `reduce`, `filter`

Bug fixes:
* Fix incorrect evaluation of constants during simplification

Improvements:
* Improve solver shuffle around singularities and errors

### 0.9.17 — 2026-03-10

Extended support for quotients, algebraic notation for array/list indexing (e.g. 'L(1;2)' ), copy-paste support.

### 0.9.16 — 2026-03-07

0.9.16 adds a number of new features and bug fixes, detailed in the release notes in the built-in help file. The primary new features include: prime numbers and factorization, displaying keyboard shortcuts in the built-in help, extended rational approximation (→Qπ).

### 0.9.14 — 2025-11-10

Immediate rendering for off-screen graphics, bug fixes.

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## More apps by Christophe de Dinechin

- [DB48X](https://appshunter.io/ios/app/db48x/id6615086535)
- [DB40X](https://appshunter.io/ios/app/db40x/id6624315901)

All apps by Christophe de Dinechin: https://appshunter.io/developer/1761608161

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-24.*